Kenmore dryer, 110.86983810 TIMER WILL NOT ADVANCE.

I have a Kenmore dryer, 110.86983810. The timer will not advance in any cycle – moisture-sensing, timed drying, and cool air.

I have replaced the timer which has not helped. I checked the voltage coming to the black wires from the motor (to terminals W and WB). The voltage when the dryer was plugged in and running during the cool air cycle was 0. (I was expecting 120v). Otherwise the dryer is heating well and functioning normally.

What do you think is the problem? Thank you for your assistance. (I used to be an electrician's helper.)

The moisture sensing cycle is not the issue because you tested in the Time Dry cycle with no advance.
You also did a volt check from B to WB with no voltage reading.
If your meter is accurate you should have had voltage at these timer motor terminals while set for time dry and running.
You can make a 120 volts jumper cord and direct wire the timer motor to see if it runs.

that model uses an "odd" Dryness Control Board that could prevent the Timer Motor operation in the Regular Timed Dry Cycle
Does it work OK in the Auto Dry cycles ?
If it were my Dryer, I would leave the Board (if Auto Dry works)
and place a ON / OFF jumper Switch across DC1 to DC5,